Encoding recording data on optical disks

ABSTRACT

An encoding method for recording gap regions or sectors having repeated data is disclosed. At least one sector is entirely encoded and stored in a memory buffer of the optical recording system. If the currently encoded are gap regions or sector having repeated data embedded in the fields of user data, only those portions affected by the modified header will be encoded to derive associated P code and Q code. The error detection code is firstly generated in the mode 1 standard when a gap region is encoded. P code is then encoded for those regions affected by the sequentially modified header and error detection code, while associated Q code is then derived according the modified header, error detection code, and P code. In the mode 2 form 1 and mode form 2 standards, only those regions affected by the sequentially modified header should be re-encoded again. Since the remaining portions employ the same data as the last encoded one in the memory buffer so that the encoding performance would be significantly upgraded whatever encoding standards are employed.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is a reissue application for commonly assignedU.S. Pat. No. 7,023,784, issued Apr. 4, 2006 from U.S. patentapplication Ser. No. 10/400,574, filed on Mar. 28, 2003.

BACKGROUND

1. Field of the Invention

The present invention is related to an encoding method for recordingdata on a compact disk (CD), and more particularly, to an encodingmethod that can efficiently upgrade the data encoding performance whenan optical recording system records gap regions or sectors includingrepeated data onto a compact disk.

2. Background of the Invention

Recently, opticalOptical disks have become an important and popularstorage media for holding a huge volume of data. Generally, the datathat is ready to be recorded onto a compact disk is divided and encodedinto a plurality of sectors by following standard formats such as thesector structures shown in FIGS. 1 to 3. In these figures, the unit ofdata is byte, and there are 2352 bytes included in a sector. FIG. 1 is aschematic diagram of the first encoding form (e.g., mode 1 standard),which is adapted to encode data for application software. FIGS. 2 and 3respectively show the second encoding form (e.g., mode 2 form 1standard) and the third encoding form (e.g., mode 2 form 2 standard)that both of them are adapted for encoding video/audio data.

The conventional encoding method is described by making reference withFIG. 1. A host such as a personal computer (PC) firstly transfers a userdata 13 having 2048 bytes to an optical recording system, e.g. a compactdisk-recordable (CD-R) drive or a compact disk-rewritable (CD-RW) drive.The optical recording system then generates a synchronous code 11 and aheader 12 for the user data 13, while an error detection code 14 (EDC)is generated according to the synchronous code 11, header 12, and theuser data 13. Sequentially, after a zero code 15 is attached (with4-byte length), an error correction code 16 (ECC) is next generatedaccording to the header 12, user data 13, EDC 14, and the zero code 15.The first encoding form (or the C3 encoding procedure) is completed whenthe above encoding procedure terminates, wherein the ECC 16 includes a Pcode 161 (P-parity check code) and a Q code 162 (Q-parity check code).Sequential encoding procedures, including C2 and C1 encoding procedures,are then performed to the complete encoded data under the mode 1standard.

Sometimes the optical recording system will record so-called gap regionson the compact disk within the data recording procedures. For example,when an audio or music CD is recording, the optical recording system mayrecord a lot of gap regions (e.g., 2 seconds, about 150 gap regions)adjacent to a just recorded song before recording another one. Besides,if the so-called buffer-under-run occurs during data recodingoperations, the optical recording system will also record gap regions onthe current compact disk and wait for the data stored in buffers reachesto a predetermined threshold again. In comparison with a normal sector,these gap regions usually contain repeated information (e.g., all bit0's) stored therein, and contents of the gap regions will be repeatedexcept the header 12, 22 and 32, the EDC 14, 25 and 35, and the ECC 16and 22.

As shown in FIG. 1, when a sector is being encoded, the ECC 16 will begenerated according the header 12, user data 13, EDC 14 and zero code15, while the ECC 26 will be derived according to the user data 24 andEDC 25 as shown in FIG. 2. However, since the the user data 13, 24 and34 occupy most of the entire sector portions and they usually storerepeated data as mentioned above, the conventional approach is obviousan inefficient way for encoding information due to a time-cost as wellas resource-costapproach is employed for the optical recording system.

Accordingly, the aforementioned conventional encoding scheme obviouslyincludes many disadvantages waiting for further improvements. Thepresent invention therefore discloses a solution for overcoming thesedisadvantages of the prior art scheme.

SUMMARY OF THE INVENTION

The principal object of the present invention is to provide an encodingmethod for recording data on a compact disk so that the encodingefficiency can be significantly upgradedthan before.

In the preferred embodiment, the disclosed method provides an encodingmethod adapted for recording gap regions or sectors having repeated datathat these repeated data are not always entirely encoded so as toupgrade encoding efficiency.

In accordance with the present invention, the optical recording systemwill encode at least one gap region or sector having repeated datafirstly. The non-repeated portions such as the headers of the followinggap regions or sectors in memory buffer of the optical recording systemare then modified. Encoding procedures are then actuated for thoseportions affected by the modified header, while those unaffectedportions are not encoded again since the unaffected ones in the memorybuffer are not changed during the encoding procedures. The currentencoded sector or gap region is then delivered to actuate followingencoding procedures before being recorded onto a compact disc

In the embodiment, when a header is modified in the memory buffer underthe mode 1 standard when gap regions are encoded, the error detectioncode will be changed according to the modified heard headersimultaneously. The optical recording system then only encodes thoseportions affected by the modified header and error detection code. Inanother embodiment, since only the header changes as different gapregions in the mode 2 form 1 standard and the mode 2 form 2 standard,only those portions affected by the modified headers will be encoded bythe optical recording system. Total time-cost regarding the encodingprocedures will be significantly reduced since the bus bandwidths foraccessing data is significantly reduced.

Numerous additional features, benefits and details of the method of thepresent invention are described in the detailed description whichfollows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of the first encoding form;

FIG. 2 is a diagram of the second encoding form;

FIG. 3 is a diagram of the third encoding form; and

FIG. 4 is a flow chart of the preferred embodiment according to thepresent invention.

Table 1 is a coding table of the first encoding form 1.

Table 2 is a coding table of the Q code of the first encoding form 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Please refer to FIG. 1 and by making reference to Tables 1 and 2. Table1 is the coding table of the mode 1 standard (the sync code 11 of thefirst encoding form is not included in Table 1), while Table 2 is thecoding table of the Q code 162 of the mode 1 standard. The wordaddresses (a word is composed of two bytes) are respectively marked as0˜1169 in Table 1, and the contents of the first encoding form is mappedinto Table 1 orderly. For example, the header 12 is stored in words 0˜1,the user data 13 employs 1024 words 2˜1025 for storing purpose, theerror detection code 14 is stored in words 1026˜1027, while the fieldsof words 1028˜1031 is used to store zero code 15. Furthermore, the Pcode 161 and the Q code of the error correction code 16 are respectivelystored in words 1032˜1117 and 1118˜1169.

Since all information of the gap regions is stored into a memory bufferof the optical recording system for encoding purpose purposes, theoperating flows of the embodiment are described based on the memorybuffer in the following paragraphs. The first embodiment demonstratesthe operating flows when the optical recording system encodes data underthe mode 1 standard. During the operation of recording data onto acompact disk, the optical recording system will encode whole portions ofthe first sector (or, at least one sector stored in the memory buffercurrently). Thereafter, the optical recording system will generate asynchronous code 11 and a header 12 for the user data 13, while an errordetection code 14 (EDC) is then derived according to the synchronouscode 11, header 12, and the user data 13 when the mode 1 standard isfollowed. If gap regions are currently encoded, only the header 12 ofthe first sector (which indicates the first gap region now) will bechanged (in fact, the content of header 12 will plus an integer one toindicate the header of the next gap region), which will also affect theerror detection code under the mode 1 standard. Accordingly, the opticalrecording system will partially encode the next gap region to thosenon-repeated potions portions (or affected portions), e.g. thoseportions affected by the modified header 12 (such column and rowsincluding information regarding the modified header 12, EDC 14 and Pcode 161 under the mode 1 standard). All gap regions are encoded byfollowing the aforementioned steps so that encoding efficiency will besignificantly upgraded since most of the entire sectors do not need tobe repeatedly encoded except the first gap region. On the other hand, ifthe currently encoded sector are is not a gap region, error correctioncode (ECC) 16 including P code and Q code are then derived by theoptical recording system based on header 12, user data 13, EDC 14, andzero code 15. Please note that the optical recording system may employthe disclosed method of the embodiments for encoding sectors havingrepeated data embedded in their user data 13 in order to decreaserequired time-cost regarding encoding procedures. Any ordinary personhaving skills in the art may modify the embodiment as applications butall similar rearrangements and modifications within the spirits spiritof the embodiment should included in the appended claims.

The first encoding operation when encoding sectors having non-repeateddata (i.e., non-repeated data in their fields of user data 13) isdescribed as follows. Please refer to Table 1 firstly. The opticalrecording system will generate P code 161 according to the data storedin rows R0˜23, while the derived P code is then stored into rows R24˜25Taking column C0 as an example (the other columns will be manipulated inthe same way), the optical recording system will encode the data inaddresses 0, 43, 86 . . . 989 to derive corresponding parity check codesbefore storing in addresses 1032 and 1075.

Please now refer to Table 2. The optical recording system will generateQ code 162 according to the data in column C′0˜C′42 after P code 161 isderived, while the derived Q code 162 is then stored into columnC′43˜44. Taking column R′0 as an example (the other rows will be encodedas the same manner), the optical recording system will encode the datain addresses 0, 44, 88 . . . 730 to generate corresponding parity checkcodes, while the derived parity check codes are then stored in addresses1118 and 1144.

On the other hand, the second encoding operation when encoding gapregions or sectors having repeated data is described as follows. Theoptical recording system will firstly detect whether the gap region orsector encompasses repeated information or not. Please note that the gapregions basically including repeated data stored therein, this detectionwill be a step for guarantee purpose. If the detected sector or gapregion is not a repeated one, the first encoding operation will beperformed, otherwise the optical recording system will perform thesecond encoding operation to generate the error correction code 16 forthose portions unaffected by the modified header 12.

Taking the first encoding form as an example. Since the header 12 inaddresses 0˜1, the error detection code 14 in addresses 1026˜1027 andtheir corresponding parity check codes in addresses 1032, 1033, 1069,1070, 1075, 1076, 1112 and 1113 are changed in the memory buffer whenrecording gap regions under mode 1 standard, the optical recordingsystem only have to encode those portions affected by the aboveaddresses during the second encoding operation.

For the sake of clarity, the encoding procedures of those portionsaffected by the modified header 12 are described further in thefollowing.

(a) Firstly, the optical recording system generates the P code 161,according to the header 12 and the error detection code 14. Referring toTable 1, since there are columns C0, C1, C37 and C38 include theinformation regarding modified header 12 and EDC 14, the opticalrecording system generates the parity check codes for the data incolumns C0, C1, C37 and C38 and then stores the derived parity checkcodes in addresses 1032, 1033, 1069, 1070, 1075, 1076, 1112 and 1113.Taking column C0 for example, the optical recording system will generateparity check codes according to the data in addresses 0, 43, 86 . . .989, while these parity check codes are then stored into the addresses1032 and 1075.

(b) The optical recording system generates the Q code 162 according tothe header 12, the error detection code 14 and the P code 161 sincemodifications to P code 161 will cause modifications to Q code 162simultaneously. Referring to Table 2, the optical recording systemgenerates the Q code 162 according to the data in eight rows R′0, R′11,R′12, R′13, R′14, R′23, R′24 and R′25 and then stores the generatedparity check codes in addresses 1118, 1129, 1130, 1131, 1132, 1141,1142, 1143, 1144, 1155, 1156, 1157, 1158, 1167, 1168 and 1169,respectively. Taking row R′0 for example, the optical recording systemgenerates parity check codes for the data in addresses 0, 44, 88 . . .730 and then stores these parity check codes into the addresses 1118 and1144. As known by an ordinary person having skills in the art, themodified header 12 will directly affect two rows by itself, andsimultaneously affect two rows regarding the EDC 14 under the mode 1standard. Since the P code 161 and Q code 162 will be affected to varytheir currently stored values by the modified header 12 and EDC 14,eight additional rows are changed and need to be encoded in theembodiment. Finally, only aforementioned eight rows require to beencoded since some overlapped rows must be eliminated.

Please now refer to FIGS. 1 and 4 and by making reference to Tables 1and 2, wherein FIG. 4 is a flow chart of the encoding method inaccordance with the present invention. The encoding method of thepresent invention includes those steps as follows. Please note that themethod described below is an embodiment of the present inventionaccording to the mode 1 standard as shown in FIG. 1. However, inpractice, this method also can apply to mode 2 form 1 and the mode 2form 2 standards respectively shown in FIGS. 2 and 3, which may bringmore encoding efficiency than that of the mode 1 standard. Detaileddescriptions regarding the use of mode 2 form 1 and mode 2 form 2standards are given later.

Step 401: During data recording operations, the optical recording systemwill encode the ready-for-encoding sector in the memory buffer to deriveEDC 14 firstly. Of course, at least one sector (whether a gap region ora normal sector) should be encoded by using whole sector data. Forexample, there may create memory buffer having enough spaces to storethree sectors in practical implementations, and the optical recordingsystem will perform encoding procedures to all these three sectorsbefore the operating flow of FIG. 4 starts. Please note that only theheaders 12 of the three gap regions are different since they are givenby sequential numerals, e.g. 00000001h, 00000002h, 00000003h are givenfor these three gap regions. The optical recording system will modifythe header 00000001h of the first gap region to be 00000004h for thepurpose of indicating the fourth gap region after the first gap regionhas been delivered to arisen the following C2 and C1 encodingprocedures. Similarly, the fifth and sixth gap regions may be encoded byrespectively modifying the header 00000002h and 00000003h to be00000005h, 00000006h after the second and third gap regions beingdelivered. An artisan having ordinary skills in the art may modify theembodiment as requirements and applications dictate.

Step 402: The optical recording system then check checks whether thenext sector ready for recording indicates a gap region (or a sectorhaving repeated data) or not. This step will be one for achieving theguarantee purpose as above-mentioned when encoding gap regions. Based ondecision result, the optical recording system performs the followingStep 403 if the next sector data does not indicate a gap region,otherwise the following Step 404 will be performed if a gap region isgoing to be encoded.

Step 403: A first encoding operation is performed, which also includesSteps 4031 and 4032 as follows.

Step 4031: Referring to Table 1, the optical recording system willperform an encoding operation to derive the P code 161 according torelated portions of the encoding format in Table 1. In other words, thedata in columns C0˜C42 are sequentially encoded along the directionindicated by rows R0˜R23, while the generated parity check codes arethen stored in rows R24˜25 Taking column C0 as an example (of course theother columns will be encoded as the same manner), the optical recordingsystem will encode the data in addresses 0, 43, 86 . . . 989 andgenerate corresponding parity check codes that are stored in addresses1032 and 1075 as mentioned above.

Step 4032: Referring to Table 2, the optical recording system wouldgenerate the Q code 162. Taking column R′0 as an example, the opticalrecording system will encode the data mapped to addresses 0, 44, 88 . .. 730 and generate a corresponding parity check code stored in addresses1118 and 1144. The encoding procedure of the embodiment is completeafter this step terminates, while the optical recording system returnsto Step 401 for encoding the successive sectors or gap regions.

Step 404: The optical recording system will execute the second encodingoperation, which can be divided into separate Steps 4041, 4042 and 4043described as follows.

Step 4041: By comparing with the former encoded data, the opticalrecording system will firstly detect whether the ready-for-encodingsector or gap region encompasses repeated data or not. This step may beeliminated or remained for confirmation purpose as applications sincethe optical recording system understands whether the currently encodingsector is a gap region (or a sector having repeated data stored in thefiled of user data 13) or not. The optical recording system will switchto Step 4031 to perform the first encoding operations if the currentencoding sector or gap region does not include repeated data. Otherwisethe optical recording system will go on the following Step 4042.

Step 4042: The optical recording system generates the parity check code,i.e., the P code 161, according to those non-repeated portions (or“affected” portions) that are affected by the modified header 12 and EDC14. Please now refer to Table 1, the optical recording system generatesthe parity check code according to the data mapped to columns C0, C1,C37 and C 38 and stores the generated parity check code in addresses1032, 1033, 1069, 1070, 1075, 1076, 1112 and 1113. Taking column C0 forexample, the optical recording system will generate a parity check codemapped to addresses 1032 and 1075 according to the data mapped toaddresses 0, 43, 86 . . . 989. Moreover, the optical recording systemwill generate the parity check code of the P code 161 corresponding tothe repeated portions by copying that of the former encoding data.

Step 4043: The optical recording system generates the Q code 162according to the non-repeated portions affected by the modified header12 and EDC 14. Please note that only the header 12 mapped to addresses0˜1, the EDC 14 mapped to addresses 1026˜1027 and their correspondingparity check code (P code) mapped to addresses 1032, 1033, 1069, 1070,1075, 1076, 1112 and 1113 are non-repeated portions here. Please referto Table 2 now, the optical recording system will generate the Q code162 according to the data mapped to rows R′0, R′11, R′12, R′13, R′14,R′23, R′24 and R′25 and then stores the generated parity check code inAddresses 1118, 1129, 1130, 1131, 1132, 1141, 1142, 1143, 1144, 1155,1156, 1157, 1158, 1167, 1168 and 1169. Taking row R′0 for example, theoptical recording system will generate a parity check code mapped toaddresses 1118 and 1144 according to the data in addresses 0, 44, 88 . .. 730. Moreover, the optical recording system does not need to generateQ code 162 for those repeated portions since the Q code 162 regardingthe repeated portions has been calculated and stored in the memorybuffer already when encoding the first gap region. The second encodingoperation is complete when this step terminates and the current encodedgap region can be delivered for recording onto a compact disc. Finallythe optical recording system returns to Step 401 for encoding thesequential gap regions.

Since the encoding method of the present invention only encodes thenon-repeated portions of the gap region, time-cost for encoding the gapregion will be effectively reduced so that the data encoding efficiencycan be significantly upgraded due to the system resource beingefficiently used. In another embodiment, there is no additional portionin the memory buffer affected by the modified headers 22 and 32 underthe mode 2 form 1 and mode 2 form 2 standards, respectively. In otherwords, the EDC 25 and ECC 26 in the mode 2 form 1 standard, and the EDC35 in the mode 2 form 2 standard will remains the same as the formerencoded results when only the header is modified. Therefore, only thoseportions related to the headers require to be encoded by the opticalrecording system, that is, only those rows and columns that include themodified header need to be encoded in these two embodiment. Totallyencoding time will be significantly reduced since the bus bandwidths foraccessing data will be significantly reduced whatever mode 1, mode 2form 1, or mode 2 form 2 standards are employed.

Although the present invention has been described with reference to thepreferred embodiment thereof, it will be understood that the inventionis not limited to the details thereof. Various substitutions andmodifications have been suggested in the foregoing description, andother will occur to those of ordinary skill in the art. Therefore, allsuch substitutions and modifications are embraced within the scope ofthe invention as defined in the appended claims.

TABLE 1 PRIOR ART C0 C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 C14 R0 01 2 3 4 5 6 7 8 9 10 11 12 13 14 R1 43 44 45 46 47 48 49 50 51 52 53 5455 56 57 R2 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 R3 129 130 131132 133 134 135 136 137 138 139 140 141 142 143 R4 172 173 174 175 176177 178 179 180 181 182 183 184 185 186 R5 215 216 217 218 219 220 221222 223 224 225 226 227 228 229 R6 258 259 260 261 262 263 264 265 266267 268 269 270 271 272 R7 301 302 303 304 305 306 307 308 309 310 311312 313 314 315 R8 344 345 346 347 348 349 350 351 352 353 354 355 356357 358 R9 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401R10 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 R11 473474 475 476 477 478 479 480 481 482 483 484 485 486 487 R12 516 517 518519 520 521 522 523 524 525 526 527 528 529 530 R13 559 560 561 562 563564 565 566 567 568 569 570 571 572 573 R14 602 603 604 605 606 607 608609 610 611 612 613 614 615 616 R15 645 646 647 648 649 650 651 652 653654 655 656 657 658 659 R16 688 689 690 691 692 693 694 695 696 697 698699 700 701 702 R17 731 732 733 734 735 736 737 738 739 740 741 742 743744 745 R18 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788R19 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 R20 860861 862 863 864 865 866 867 868 869 870 871 872 873 874 R21 903 904 905906 907 908 909 910 911 912 913 914 915 916 917 R22 946 947 948 949 950951 952 953 954 955 956 957 958 959 960 R23 989 990 991 992 993 994 995996 997 998 999 1000 1001 1002 1003 R24 1032 1033 1034 1035 1036 10371038 1039 1040 1041 1042 1043 1044 1045 1046 R25 1075 1076 1077 10781079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 R26 1118 11191120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 R271144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 11571158 C15 C16 C17 C18 C19 C20 C21 C22 C23 C24 C25 C26 C27 C28 C29 R0 1516 17 18 19 20 21 22 23 24 25 26 27 28 29 R1 58 59 60 61 62 63 64 65 6667 68 69 70 71 72 R2 101 102 103 104 105 106 107 108 109 110 111 112 113114 115 R3 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158R4 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 R5 230231 232 233 234 235 236 237 238 239 240 241 242 243 244 R6 273 274 275276 277 278 279 280 281 282 283 284 285 286 287 R7 316 317 318 319 320321 322 323 324 325 326 327 328 329 330 R8 359 360 361 362 363 364 365366 367 368 369 370 371 372 373 R9 402 403 404 405 406 407 408 409 410411 412 413 414 415 416 R10 445 446 447 448 449 450 451 452 453 454 455456 457 458 459 R11 488 489 490 491 492 493 494 495 496 497 498 499 500501 502 R12 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545R13 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 R14 617618 619 620 621 622 623 624 625 626 627 628 629 630 631 R15 660 661 662663 664 665 666 667 668 669 670 671 672 673 674 R16 703 704 705 706 707708 709 710 711 712 713 714 715 716 717 R17 746 747 748 749 750 751 752753 754 755 756 757 758 759 760 R18 789 790 791 792 793 794 795 796 797798 799 800 801 802 803 R19 832 833 834 835 836 837 838 839 840 841 842843 844 845 846 R20 875 876 877 878 879 880 881 882 883 884 885 886 887888 889 R21 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932R22 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 R23 10041005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018R24 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 10591060 1061 R25 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 11001101 1102 1103 1104 R26 1133 1134 1135 1136 1137 1138 1139 1140 11411142 1143 R27 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 C30C31 C32 C33 C34 C35 C36 C37 C38 C39 C40 C41 C42 R0 30 31 32 33 34 35 3637 38 39 40 41 42 R1 73 74 75 76 77 78 79 80 81 82 83 84 85 R2 116 117118 119 120 121 122 123 124 125 126 127 128 R3 159 160 161 162 163 164165 166 167 168 169 170 171 R4 202 203 204 205 206 207 208 209 210 211212 213 214 R5 245 246 247 248 249 250 251 252 253 254 255 256 257 R6288 289 290 291 292 293 294 295 296 297 298 299 300 R7 331 332 333 334335 336 337 338 339 340 341 342 343 R8 374 375 376 377 378 379 380 381382 383 384 385 386 R9 417 418 419 420 421 422 423 424 425 426 427 428429 R10 460 461 462 463 464 465 466 467 468 469 470 471 472 R11 503 504505 506 507 508 509 510 511 512 513 514 515 R12 546 547 548 549 550 551552 553 554 555 556 557 558 R13 589 590 591 592 593 594 595 596 597 598599 600 601 R14 632 633 634 635 636 637 638 639 640 641 642 643 644 R15675 676 677 678 679 680 681 682 683 684 685 686 687 R16 718 719 720 721722 723 724 725 726 727 728 729 730 R17 761 762 763 764 765 766 767 768769 770 771 772 773 R18 804 805 806 807 808 809 810 811 812 813 814 815816 R19 847 848 849 850 851 852 853 854 855 856 857 858 859 R20 890 891892 893 894 895 896 897 898 899 900 901 902 R21 933 934 935 936 937 938939 940 941 942 943 944 945 R22 976 977 978 979 980 981 982 983 984 985986 987 988 R23 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 10291030 1031 R24 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 10721073 1074 R25 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 11151116 1117 R26 R27

TABLE 2 PRIOR ART C′0 C′1 C′2 C′3 C′4 C′5 C′6 C′7 C′8 C′9 C′10 C′11 C′12C′13 C′14 R′0 0 44 88 132 176 220 264 308 352 396 440 484 528 572 616R′1 43 87 131 175 219 263 307 351 395 439 483 527 571 615 659 R′2 86 130174 218 262 306 350 394 438 482 526 570 614 658 702 R′3 129 173 217 261305 349 393 437 481 525 569 613 657 701 745 R′4 172 216 260 304 348 392436 480 524 568 612 656 700 744 788 R′5 215 259 303 347 391 435 479 523567 611 655 699 743 787 831 R′6 258 302 346 390 434 478 522 566 610 654698 742 786 830 874 R′7 301 345 389 433 477 521 565 609 653 697 741 784829 873 917 R′8 344 388 432 476 520 564 608 652 696 740 784 828 872 916960 R′9 387 431 475 519 563 607 651 695 739 783 827 871 915 959 1003R′10 430 474 518 562 606 650 694 738 782 826 870 914 958 1002 1046 R′11473 517 561 605 649 693 737 781 825 869 913 957 1001 1045 1089 R′12 516560 604 648 692 736 780 824 868 912 956 1000 1044 1088 14 R′13 559 603647 691 735 779 823 867 911 955 999 1043 1087 13 57 R′14 602 646 690 734778 822 866 910 954 998 1042 1086 12 56 100 R′15 645 689 733 777 821 865909 953 997 1041 1085 11 55 99 143 R′16 688 732 776 820 864 908 952 9961040 1084 10 54 98 142 186 R′17 731 774 819 863 907 951 995 1039 1083 953 97 141 185 229 R′18 774 818 862 906 950 994 1038 1082 8 52 96 140 184228 272 R′19 817 861 905 949 993 1037 1081 7 51 95 139 183 227 271 315R′20 860 904 948 992 1036 1080 6 50 94 138 182 226 270 314 358 R′21 903947 991 1035 1079 5 49 93 137 181 225 269 313 357 401 R′22 946 990 10341078 4 48 92 136 180 224 268 312 356 400 444 R′23 989 1033 1077 3 47 91135 179 223 267 311 355 399 443 487 R′24 1032 1076 2 46 90 134 178 222266 310 354 398 442 486 530 R′25 1075 1 45 89 133 177 221 265 309 353397 441 485 529 573 C′15 C′16 C′17 C′18 C′19 C′20 C′21 C′22 C′23 C′24C′25 C′26 C′27 C′28 C′29 R′0 660 704 748 792 836 880 924 968 1012 10561100 26 70 114 158 R′1 703 747 791 835 879 923 967 1011 1055 1099 25 69113 157 201 R′2 746 790 834 878 922 966 1010 1054 1098 24 68 112 156 200244 R′3 789 833 877 921 965 1009 1053 1097 23 67 111 155 199 243 287 R′4832 876 920 964 1008 1052 1096 22 66 110 154 198 242 286 330 R′5 875 919963 1007 1051 1095 21 65 109 153 197 241 285 329 373 R′6 918 962 10061050 1094 20 64 108 152 196 240 284 328 372 416 R′7 961 1005 1049 109319 63 107 151 195 239 283 327 371 415 459 R′8 1004 1048 1092 18 62 106150 194 238 282 326 370 414 458 502 R′9 1047 1091 17 61 105 149 193 237281 325 369 413 457 501 545 R′10 1090 16 60 104 148 192 236 280 324 368412 456 500 544 588 R′11 15 59 103 147 191 235 279 323 367 411 455 499543 587 631 R′12 58 102 146 190 234 278 322 366 410 454 498 542 586 630674 R′13 101 145 189 233 277 321 365 409 453 497 541 585 629 673 717R′14 144 188 232 276 320 364 408 452 496 540 584 628 672 716 760 R′15187 231 275 319 363 407 451 495 539 583 627 671 715 759 803 R′16 230 274318 362 406 450 494 538 582 626 670 714 758 802 846 R′17 273 317 361 405449 493 537 581 625 669 713 757 801 845 889 R′18 316 360 404 448 492 536580 624 668 712 756 800 844 888 932 R′19 359 403 447 491 535 579 623 667711 755 799 843 887 931 975 R′20 402 446 490 534 578 622 666 710 754 798842 886 930 974 1018 R′21 445 489 533 577 621 665 709 753 797 841 885929 973 1017 1061 R′22 488 532 576 620 664 708 752 796 840 884 928 9721016 1060 1104 R′23 531 575 619 663 707 751 795 839 883 927 971 10151059 1103 29 R′24 574 618 662 706 750 794 868 882 926 970 1014 1058 110228 72 R′25 617 661 705 749 793 837 881 925 969 1013 1057 1101 27 71 115C′30 C′31 C′32 C′33 C′34 C′35 C′36 C′37 C′38 C′39 C′40 C′41 C′42 C′43C′44 R′0 202 246 290 334 378 422 466 510 554 598 642 686 730 1118 1144R′1 245 289 333 377 421 465 509 553 597 641 685 729 773 1119 1145 R′2288 332 376 420 464 508 552 596 640 684 728 772 816 1120 1146 R′3 331375 419 463 507 551 595 639 683 727 771 815 859 1121 1147 R′4 374 418462 506 550 594 638 682 726 770 814 858 902 1122 1148 R′5 417 461 505549 593 637 681 725 769 813 857 901 945 1123 1149 R′6 460 504 548 592636 680 724 768 812 856 900 944 988 1124 1150 R′7 503 547 591 635 679723 767 811 855 899 943 987 1031 1125 1151 R′8 546 590 634 678 722 766810 854 898 942 986 1030 1074 1126 1152 R′9 589 633 677 721 765 809 853897 941 985 1029 1073 1117 1127 1153 R′10 632 676 720 764 808 852 896940 984 1028 1072 1116 42 1128 1154 R′11 675 719 763 807 851 895 939 9831027 1071 1115 41 85 1129 1155 R′12 718 762 806 850 894 938 982 10261070 1114 40 84 128 1130 1156 R′13 761 805 849 893 937 981 1025 10691113 39 83 127 171 1131 1157 R′14 804 848 892 936 980 1024 1068 1112 3882 126 170 214 1132 1158 R′15 847 891 935 979 1023 1067 1111 37 81 125169 213 257 1133 1159 R′16 890 934 978 1022 1066 1110 36 80 124 168 212256 300 1134 1160 R′17 933 977 1021 1065 1109 35 79 123 167 211 255 299343 1135 1161 R′18 976 1020 1064 1108 34 78 122 166 210 254 298 342 3861136 1162 R′19 1019 1063 1107 33 77 121 165 209 253 297 341 385 429 11371163 R′20 1062 1106 32 76 120 164 208 252 296 340 384 428 472 1138 1164R′21 1105 31 75 119 163 207 251 295 339 383 427 471 515 1139 1165 R′2230 74 118 162 206 250 294 338 382 426 470 514 558 1140 1166 R′23 73 117161 205 249 293 337 381 425 469 513 557 601 1141 1167 R′24 116 160 204248 292 336 380 424 468 512 556 600 644 1142 1168 R′25 159 203 247 291335 379 423 467 511 555 599 643 687 1143 1169

1. A method for encoding data ready-for-recording on a compact disk,wherein said ready-for-recording data comprises a plurality of datasectors and each of said data sector sectors having a header and a userdata, said method comprising: encoding first sector of said plurality ofdata sectors; modifying said header of a second data sector of saidplurality of data sectors, said second data sector being succeeding tosaid first data sector; partially encoding said second data sector byencoding an affected portion of said second data sector according tosaid modified header when said second sector having said user dataidentical to that of said first sector, wherein a portion of said seconddata sector that is not affected by said modified header is not variedwhen said affected portion is encoded; and encoding said second sectorby using entire data of said second sector when said second sector hasuser data non-identical to that of said first sector.
 2. The encodingmethod as claimed in claim 1 wherein said affected portion is variedwith said modified header.
 3. The encoding method as claimed in claim 2wherein an encoding form for recording said optical disk is the mode 1standard.
 4. The encoding method as claimed in claim 1 wherein saidmodified header modified according to a relationship between said firstsector and said second sector.
 5. The encoding method as claimed inclaim 4 wherein said affected portion comprises a row includinginformation being modified by said modified header and a columnincluding information being modified by said modified header.
 6. Theencoding method as claimed in claim 4 wherein said affected portioncomprises an error detection code being modified according to saidmodified header.
 7. The encoding method as claimed in claim 4 whereinsaid affected portion comprises an error correction code being modifiedaccording to said modified header.
 8. The encoding method as claimed inclaim 1 wherein said ready-for-recording data indicates a gap regionwhen all of said user data in said plurality of data sectors areidentical.
 9. The encoding method as claimed in claim 1 wherein portionof said second data sector that is not affected by said modified headerremains the same in a memory buffer of an optical recording system whenencoding said second data sector.
 10. A method of encoding a pluralityof data sectors having identical user data before an optical recordingsystem records said sector onto a compact disk comprising: encoding afirst sector of said plurality of data sectors, wherein each one of saidplurality of data sectors having a header; modifying said header of asecond data sector of said plurality of data sectors, said second datasector being succeeding to said first data sector; and partiallyencoding said second data sector by encoding an affected portion of saidsecond data sector according to said modified header, wherein a portionof said second data sector that is not affected by said modified headeris not varied when said affected portion is encoded.
 11. The encodingmethod as claimed in claim 10 wherein said affected portion is variedwith said modified header.
 12. The encoding method as claimed in claim10 wherein an encoding form for recording said optical disk is the mode1 standard.
 13. The encoding method as claimed in claim 12 wherein saidaffected portion comprises a row including information being modified bysaid modified header and a column including information being modifiedby said modified header.
 14. The encoding method as claimed in claim 12wherein said affected portion comprises an error detection code beingmodified according to said modified header.
 15. The encoding method asclaimed in claim 14 wherein said affected portion comprises an errorcorrection code being modified according to said modified header. 16.The encoding method as claimed in claim 15 wherein said currentlyencoded sector follows a standard adapted to encode applicationsoftware.
 17. The encoding method as claimed in claim 10 wherein saidready-for-recording data indicates a gap region when all of said userdata in said plurality of data sectors are identical.
 18. The encodingmethod as claimed in claim 10 wherein said portion of said second datasector that is not affected by said modified header remains the same ina memory buffer of an optical recording system when encoding said seconddata sector.
 19. A method for encoding a gap region ready-for-recordingonto a compact disk, wherein said gap region comprises a plurality ofdata sectors and each of said data sectors having a repeated user dataidentical to said other data sectors and a header that is non-identicalto said other data sectors, said method comprising: encoding a firstsector of said plurality of data sectors according to said repeated userdata and said non-repeated portion; modifying said header of a seconddata sector of said plurality of data sector according to a relationshipbetween said first sector and said second data sector, said second datasector being succeeding to said first data sector; encoding an affectedportion of said second data sector according to said modified header,wherein said affected portion is varied with said modified header; andencoding said second data sector according to an encoding form saidcompact disk being employed.
 20. The encoding method as claimed in claim19 wherein said step of encoding said affected portion of said seconddata sector comprises a step of encoding an error detection code of saidsecond data sector according to a synchronous code of said second datasector, said modified header, and said identical user data when saidencoding form is the mode 1 standard.
 21. The encoding method as claimedin claim 19 wherein a non-affected portion of said encoded result ofsaid first sector remains the same when encoding said gap region. 22.The encoding method as claimed in claim 19 wherein said step of encodingsaid affected portion of said second data sector skipped when saidencoding form is the mode 2 standard.
 23. A method for encoding dataready-for-recording on a compact disk, wherein the ready-for-recordingdata comprises multiple data sectors and the individual data sectorshave a header and a user data, the method comprising: modifying theheader of a second data sector of the multiple data sectors, the seconddata sector following a first data sector; and at least partiallyencoding the second data sector by encoding an affected portion of thesecond data sector according to the modified header if the second sectorhas identical user data to that of the first data sector, wherein aportion of the second data sector that is not affected by the modifiedheader is not varied if the affected portion is encoded.
 24. The methodof claim 23 further comprising encoding the first data sector before themodifying.
 25. The method of claim 23 further comprising encoding thesecond data sector by using substantially all data of the second datasector if the second data sector has user data that is not identical tothat of the first data sector.
 26. The method of claim 23 furthercomprising: encoding the first data sector before the modifying; andencoding the second data sector by using substantially all data of thesecond data sector if the second data sector has user data that is notidentical to that of the first data sector.
 27. A computer-readablestorage device storing computer-executable instructions that, whenexecuted, perform a method for encoding data ready-for-recording on acompact disk, wherein the ready-for-recording data comprises multipledata sectors and individual data sectors have a header and a user data,the method comprising: modifying the header of a second data sector ofthe multiple data sectors, the second data sector following a first datasector; and at least partially encoding the second data sector byencoding an affected portion of the second data sector according to themodified header if the second sector has identical user data to that ofthe first data sector, wherein a portion of the second data sector thatis not affected by the modified header is not varied if the affectedportion is encoded.
 28. The computer-readable storage device of claim 27wherein the method further comprises: encoding the first data sectorbefore the modifying; and encoding the second data sector by usingsubstantially all data of the second data sector if the second datasector has user data that is not identical to that of the first datasector.
 29. A system for encoding data ready-for-recording on a compactdisk, wherein the ready-for-recording data comprises multiple datasectors and individual data sectors have a header and a user data,comprising: a component configured to modify the header of a second datasector of the multiple data sectors, the second data sector following afirst data sector; and a component configured to encode the second datasector by encoding an affected portion of the second data sectoraccording to the modified header if the second sector has identical userdata to that of the first data sector, wherein a portion of the seconddata sector that is not affected by the modified header is not varied ifthe affected portion is encoded.
 30. A system for encoding dataready-for-recording on a compact disk, wherein the ready-for-recordingdata comprises multiple data sectors and individual data sectors have aheader and a user data, comprising: means for modifying the header of asecond data sector of the multiple data sectors, the second data sectorfollowing a first data sector; and means for at least partially encodingthe second data sector by encoding an affected portion of the seconddata sector according to the modified header if the second sector hasidentical user data to that of the first data sector, wherein a portionof the second data sector that is not affected by the modified header isnot varied if the affected portion is encoded.
 31. The system of claim30 further comprising: means for encoding the first data sector beforethe modifying; and means for encoding the second data sector by usingsubstantially all data of the second data sector if the second datasector has user data that is not identical to that of the first datasector.